Final answer:
The statement is false; high test reliability indicates low measurement error as reliability measures the consistency and precision of the test results.
Step-by-step explanation:
According to Classical Test Theory, the statement that if a test has very high reliability then the measurement error must be very high is false. In fact, high reliability of a test indicates that the measurement error is low. Reliability refers to the consistency of a measure, meaning that the test produces the same results under the same conditions. Therefore, high reliability corresponds to high precision in the measurements, and consequently, a lower measurement error.